Amnesty slams Manus detention centre

Three teenage boys are being wrongly held in the Manus Island immigration detention centre alongside adult men because of rushed assessments, Amnesty International claims.

The human rights organisation visited the Papua New Guinea island in November and released a report on Wednesday describing the facilities as a cross between a prison and military camp.

The report says 1100 male asylum seekers live in three overcrowded compounds that lack privacy and provide no shelter from tropical heat.

Amnesty International claims the immigration department is rushing age determination assessments since the introduction of a new rule that asylum seekers must be transferred to PNG within 48 hours of arriving on Christmas Island.

Amnesty International interviewed three asylum seekers who claim they're aged between 15 and 17 and are being housed in conditions that are "traumatising for people their age".

Age determination interviews on Manus Island are carried out by teleconference with officers in Australia, the report said.

The report said asylum seekers spend several hours a day queueing in the blistering sun for meals.